1. Field of the Invention
This invention relates to a scissors means, and in particular, an easily disassemblable and assemblable scissors means facilitating quick and easy separation and cleaning of the scissors halves, and easy assembly for reuse. An alternative embodiment presents a disassemblable scissors which is also more economical to manufacture.
2. Problems in the Art
Conventional scissors generally are secured together by rivets, screws, and other similar fasteners. Such rivets, screws, and the like not only serve to fasten together the scissors halves, but also function as the pivot point. Additionally, they must serve to reliably keep the scissor halves in closely adjacent position to insure optimal cutting efficiency of the scissor blades.
A primary problem with scissors is that, since the blades come together and overlap to create the cutting action, debris and other material accumulates in between the blades and in the pivot of the scissor halves. Such accumulation can reduce the efficiency of the scissors, and even affect their operability. In medical uses, there is also a problem with contamination.
Scissors which have permanent securing means, such as rivets, simply do not allow the scissor halves to be disassembled, separated, and cleaned. Portions of the scissor blades adjacent to the pivot are simply not reachable for cleaning, nor is the pivot between the blades. Even with stringent cleaning techniques, build-up of debris or material in the pivot can eventually impair pivoting of the scissor halves.
Though technically, these types of scissors are disassemblable, it requires use of tools and is generally neither quick nor easy. Debris and foreign material problems exist.
Some other types of conventional scissors, though the halves are not permanently secured, are secured in a manner not easily disassemblable. Because of the need for a strong and stable pivot, and close tolerance between the cutting blades to insure accurate and efficient cutting, many times a screw or bolt and nut arrangement is used so that the blades can be continually tightened together.
These problems are particularly acute in smaller scissors, for example, with regard to those used in medical microsurgery. Build-up of debris causing corrosion can even cause removable securing means such as screws or bolts to become locked or bound, which prevents them from being removable.
No satisfactory solution is known for a scissors which combines a stable, strong, and efficient pivot mechanism, while at the same time providing for quick and easy separation of scissor halves without the need for tools. The problem is significant, especially in fields of use such as medical applications.
It is known that in some larger shearing or cutting devices, such as garden shears or the like, the halves of the instrument are disassemblable. However, this is accomplished by requiring a slot in one half, and a permanently attached stem and stem head on the other half. The head is elongated along one axis, and the slot is positioned on the one scissor half so that when the halves are rotated almost perpendicular to one another, the stem head is removable from the slot, allowing the scissor halves to be separated. When the halves are assembled, the stem head cannot be removed from the slot during the normal cutting range of the scissors. Somewhat of a similar configuration is shown in U.S. Pat. No. 2,619,965 for larger type scissors used in surgery. This solution is not satisfactory. Because of the necessary tolerances, the two scissor halves necessarily will have significant play between them. Therefore, this type of arrangement does not allow the scissors to be manufactured to optimum accuracy. Also, the stem head represents a projection from the side of the scissors which is many times disadvantageous.
Other medical instruments such as those seen in U.S. Pat. No. 3,550,595 have separability of two halves of the instrument as a feature, but the instrument halves are joined at their rear ends and the pivot consists only of a slot insertable over a pin in the other half. Thus, similar problems of play between halves of the instrument, and the problem of the two halves being separated unintentionally during use exist.
There is therefore a real need for a solution to the problems discussed above. It is therefore a primary object of the present invention to provide a scissor means which improves over and solves the problems and deficiencies in the art.
Another object of the invention is to provide a scissors means which is easily disassemblable and assemblable.
A further object of the present invention is to provide a scissors means which is stable, accurate, and efficient.
Another object of the present invention is to provide a scissors means which is easily disassembled and assembled without having to orientate scissors halves to extreme positions, or to require tools or other items to separate halves.
A further object of the present invention is to provide a scissors means which is easily and completely cleanable and serviceable.
Another object of the present invention is to provide a scissor means which is economical to manufacture, has a minimum of parts and is durable.
These and other objects, features and advantages of the present invention will become apparent with reference to the accompanying specification and drawings.